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71.
Aldosterone has been implicated as one of the mediators of cardiovascular injury in various diseases. This study examines whether mineralocorticoid antagonism ameliorates or prevents the adverse cardiac effects of hypertension and aging. Male 22-wk-old spontaneously hypertensive rats (SHR) were divided into two groups, 15 rats in each. One group received no treatment; the other was given eplerenone ( approximately 100 mg.kg(-1).day(-1)). At the age of 54 wk, indexes of cardiovascular mass, systemic and regional hemodynamics, including coronary, left ventricular function, and myocardial collagen content, were determined in all rats. Hemodynamic studies were done in conscious rats. Arterial pressure was lowered only slightly in eplerenone-treated rats, and cardiac output and total peripheral resistance did not differ from control rats. Left and right ventricular and aortic mass indexes were unaffected by eplerenone; however, concentration of hydroxyproline in the right and left ventricle was decreased significantly (P < 0.05) by eplerenone. This was accompanied by an improvement in left ventricular diastolic function and coronary hemodynamics. In conclusion, long-term therapy with the mineralocorticoid receptor antagonist eplerenone ameliorated adverse cardiac effects of both hypertension and aging in SHR. Thus reduction in myocardial fibrosis, paralleled by improvements in left ventricular function and coronary hemodynamics, was observed in eplerenone-treated SHR.  相似文献   
72.
The article reports the chemical composition, antioxidant, six key enzymes inhibitory and antimicrobial activities of two solvent extracts (water and methanol) of leaves and stem bark of Uapaca togoensis. For chemical composition, methanol extract of stem bark exhibited significant higher total phenolic (129.86 mg GAE/g) and flavanol (10.44 mg CE/g) contents. Methanol extract of leaves and water extract of stem bark showed high flavonoids (20.94 mg RE/g) and phenolic acid (90.40 mg CAE/g) content, respectively. In addition, HPLC-ESI-TOF-MS analysis revealed that U. togoensis was rich in procyanidins. The methanol and water extracts of stem bark had overall superior antioxidant activity; however, only methanol extract of stem bark showed higher inhibition of cholinesterase (AChE: 2.57 mg GALAE/g; BChE: 4.69 mg GALAE/g), tyrosinase (69.53 mg KAE/g) and elastase (2.73 mmol CE/g). Potent metal chelating ability was showed by water extract of leaves (18.94 mg EDTAE/g), higher inhibition of amylase was detected for water extracts of leaves (0.94 mmol ACAE/g) and stem bark (0.92 mmol ACAE/g). The tested extracts have shown wide-spectrum antibacterial properties and these effects have shown to be more effective against Aspergillus ochraceus, Penicillium funiculosum, Trichoderma viride, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The results revealed that the antioxidant, enzyme inhibitory and antimicrobial activities depended on the extraction solvents and the parts of plant. Bioinformatics analysis on the 17 major compounds showed modulation of pathway associated with cancer. In brief, U. togoensis might be valuable as potential source of natural agents for therapeutic application.  相似文献   
73.
Small ubiquitin-like modifier (SUMO) is a member of the superfamily of ubiquitin-like polypeptides that become covalently attached to various intracellular target proteins as a way to alter their function, location, and/or half-life. Here we show that the SUMO conjugation system operates in plants through a characterization of the Arabidopsis SUMO pathway. An eight-gene family encoding the SUMO tag was discovered as were genes encoding the various enzymes required for SUMO processing, ligation, and release. A diverse array of conjugates could be detected, some of which appear to be SUMO isoform-specific. The levels of SUMO1 and -2 conjugates but not SUMO3 conjugates increased substantially following exposure of seedlings to stress conditions, including heat shock, H(2)O(2), ethanol, and the amino acid analog canavanine. The heat-induced accumulation could be detected within 2 min from the start of a temperature upshift, suggesting that SUMO1/2 conjugation is one of the early plant responses to heat stress. Overexpression of SUMO2 enhanced both the steady state levels of SUMO2 conjugates under normal growth conditions and the subsequent heat shock-induced accumulation. This accumulation was dampened in an Arabidopsis line engineered for increased thermotolerance by overexpressing the cytosolic isoform of the HSP70 chaperonin. Taken together, the SUMO conjugation system appears to be a complex and functionally heterogeneous pathway for protein modification in plants with initial data indicating that one important function may be in stress protection and/or repair.  相似文献   
74.
Alveolar bone loss (RRR) is a continuous process following tooth extraction, more pronounced during the first few months after the tooth extraction than later. The RRR in the mandible is twice that of the maxilla during a 1-year period and the mandibular: maxillary resorption ratio increases further to 4:1. So far, the etiology of RRR has not been elucidated. It has been speculated that both systemic and local factors contribute. The aim of this study was to analyse the rate of RRR in five different regions of both jaws on lateral cephalograms of 100 complete denture wearers during a one-year period and to compare the rate of RRR between patients being edentulous over a different period of time and between patients with different body mass index. The height of residual ridges was measured on 5 different sites at the delivery of the dentures and a year later using a calibrated grid. The results revealed significant RRR in a one year period. Body mass index had no significant influence on the rate of RRR on any of the five examined sites of the maxilla or the mandible (p > 0.05), while the period of edentulousness had a significantly higher rate of resorption in first 3 sites of measurement (anteriorly) in patients being edentulous less than 1 year than in patients being edentulous for 1-10 years or for over 10 years (ANOVA, p < 0.05).  相似文献   
75.
The aim of this research was to investigate the opinions and attitudes of medical staff towards schizophrenic patients. The research included three groups of examinees, 200 physicians of various specialties, 200 nurses and technicians working in Zagreb city hospitals, and 200 3rd and 4th year students of the School of Medicine in Zagreb. Previously validated anti-stigma questionnaire was used, consisting of 25 questions divided into three thematic groups, structured and adapted to the specific requirements of this study. The results were mutually compared and statistically analyzed by applying the chi 2-test. Significant difference (p < 0.01) between the answers of physicians and those of medical students was found in questions 2, 4, 5, 6, 11, 13, 15, 16, 18, 22, 23, 25, and between physicians and nurses/technicians in answers to questions 4, 15, 22, 23. Significant difference (p < 0.01) between the answers given by nurses/technicians and medical students was found in questions 10, 13, 22, 23. The results point to the existence of prejudices and stigmatizing attitudes in all three investigated groups. The most frequent reasons for stigmatizing attitude of students are based on fear and insufficient knowledge about mental patients and schizophrenia as a disease, while there are a high percentage of positive answers to the questions on rehabilitation and resocialization. The nurses/technicians also show a high degree of mistrust towards schizophrenic patients and mostly answer with "I don't know", thus presenting insufficiently formed attitudes about the mentioned problems. The physicians in their answers confirm fear, mistrust and stigmatizing attitudes towards schizophrenic patients found in general population in Croatia. The consequences of such attitudes are the low quality of life of schizophrenic patients, and slow, often incomplete, resocialization.  相似文献   
76.
Microbial communities play an important role in cheese ripening and determine the flavor and taste of different cheese types to a large extent. However, under adverse conditions human pathogens may colonize cheese samples during ripening and may thus cause severe outbreaks of diarrhoea and other diseases. Therefore in the present study we investigated the bacterial community structure of three raw ewe''s milk cheese types, which are produced without the application of starter cultures during ripening from two production sites based on fingerprinting in combination with next generation sequencing of 16S rRNA gene amplicons. Overall a surprisingly high diversity was found in the analyzed samples and overall up to 213 OTU97 could be assigned. 20 of the major OTUs were present in all samples and include mostly lactic acid bacteria (LAB), mainly Lactococcus, and Enterococcus species. Abundance and diversity of these genera differed to a large extent between the 3 investigated cheese types and in response to the ripening process. Also a large number of non LAB genera could be identified based on phylogenetic alignments including mainly Enterobacteriaceae and Staphylococcacae. Some species belonging to these two families could be clearly assigned to species which are known as potential human pathogens like Staphylococcus saprophyticus or Salmonella spp. However, during cheese ripening their abundance was reduced. The bacterial genera, namely Lactobacillus, Streptococcus, Leuconostoc, Bifidobacterium, Brevibacterium, Corynebacterium, Clostridium, Staphylococcus, Thermoanerobacterium, E. coli, Hafnia, Pseudomonas, Janthinobacterium, Petrotoga, Kosmotoga, Megasphaera, Macrococcus, Mannheimia, Aerococcus, Vagococcus, Weissella and Pediococcus were identified at a relative low level and only in selected samples. Overall the microbial composition of the used milk and the management of the production units determined the bacterial community composition for all cheese types to a large extend, also at the late time points of cheese ripening.  相似文献   
77.
Composition of the essential oils of Rosmarinus officinalis of ten populations from the Balkan Peninsula were determined by GC/FID and GC/MS. The main constituents were 1,8‐cineole, camphor, α‐pinene, and borneol. Multivariate statistical analysis (UPGMA cluster analysis and principal‐component analysis (PCA)) revealed two major types of rosemary oil, i.e., 1,8‐cineole and camphor‐type, and two intermediate types, i.e., camphor/1,8‐cineole/borneol type and 1,8‐cineole/camphor type. The regression analyses (simple linear regression and stepwise multiple regression) have shown that, with respect to basic geographic, orographic, and 19 bioclimatic characteristics of each population, bioclimatic factor temperature of habitat represented the dominant abiogenetic factor, which, in chemical sense, led to differentiation of populations in the studied region. Also, the regression analysis have shown that some constituents of essential oils are independent of any single bioclimatic factors. However, some constituents display statistically significant correlations with some abiotic factors.  相似文献   
78.
This paper presents the results of a multivariate morphometric study of leaf anatomical characters in different populations of Sesleria rigida sensu lato in Serbia. Morphometric analyses were performed on cross-sections of 521 tiller leaves collected from 21 populations of S. rigida. Principal component analysis and canonical discriminant analysis were used to identify the structure of variability and to determine which variables discriminate between the groups. The UPGMA (unweighted pair-group average linkage) clustering analyses based on leaf anatomical characters and habitat climatic characteristics were employed to explore whether the observed anatomical differences are a result of adaptive responses. Regression analysis (linear regression) was performed to identify the level of correlation between leaf anatomical characters and basic orographic, geological, and bioclimatic habitat characteristics. DIVA-GIS software was used to extract 19 bioclimatic parameters from the WorldClim set of global climate layers. Our detailed analyses have shown that the studied populations are anatomically very well differentiated into the serpentine populations from western Serbia and carbonate populations from eastern Serbia. The regression analysis has shown that the geological substrate (serpentinites vs. carbonates) represents the most significant abiotic factor that is correlated with the anatomical differentiation of the populations in the studied area. Besides the geological substrate, bioclimatic parameters such as precipitation and habitat humidity are also highly correlated with the leaf anatomical characters, which was not the case with temperature.  相似文献   
79.
It has been proposed that certain type II restriction enzymes (REs), such as EcoRV, track the helical pitch of DNA as they diffuse along DNA, a so-called rotation-coupled sliding. As of yet, there is no direct experimental observation of this phenomenon, but mounting indirect evidence gained from single-molecule imaging of RE-DNA complexes support the hypothesis. We address this issue by conjugating fluorescent labels of varying size (organic dyes, proteins and quantum dots) to EcoRV, and by fusing it to the engineered Rop protein scRM6. Single-molecule imaging of these modified EcoRVs sliding along DNA provides us with their linear diffusion constant (D(1)), revealing a significant size dependency. To account for the dependence of D(1) on the size of the EcoRV label, we have developed four theoretical models describing different types of motion along DNA and find that our experimental results are best described by rotation-coupled sliding of the protein. The similarity of EcoRV to other type II REs and DNA binding proteins suggests that this type of motion could be widely preserved in other biological contexts.  相似文献   
80.
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